Plastic molded disposable cup lids with a drink-through feature are widely used in combination with disposable cups in retail sales of coffee, tea, cocoa and other drinks. Many such lids have an integral fold-back tab which allows a user to leave the lid completely closed until ready to consume the product contents. The user then breaks the fold-back tab free and folds it back to a locked position wherein a raised feature on the tab fits into a recess on the opposite side of the lid. Examples of such lids are found in the patents to Lombardi U.S. Pat. No. 3,977,559; DeParales U.S. Pat. No. 4,738,373 and Roberts et al. U.S. Pat. No. 5,090,584.
Most of such lids have fold-back tabs in which the distance from the periphery of the lid to the hinge is more than half of the lid radius and, in some cases, nearly a full radius. This requires the lock-back recess to be placed on the opposite side of the lid center such that the tab must extend, when folded, nearly all the way across the lid. It takes two hands to release, fold-back, and lock such a tab. This is particularly true of the Roberts et. al. and DeParales lids in which the tab extends through the rim of the lid.
To eliminate the inconvenience of such lids, some manufacturers have gone to lid designs having a pre-formed, small hole which is always open or to a flap which hinges downwardly into the cup interior when pressed by the upper lip of the user.